In retail and office environments it is common practice to use track-based systems to build the lighting system. These tracks can be suspended or recessed into the ceiling. To these tracks, lamps can be attached. Different types of these tracks are available. Some work with 230V but there are also lower voltage versions that enable different types of lamps to be used with the track. The track acts as a conductor of electricity and as a means to attach the lamps to. The lamps are usually mounted using some sort of clip. The main advantage of track-based systems is the flexibility it offers. It allows building an infrastructure of tracks which then allows lamps to be placed underneath the infrastructure of tracks built into that space.
Within the domains of architecture and interior decoration there is a clear trend towards unobtrusiveness. This also has implications or rather opportunities for the lighting domain in that within the retail and office environments there is a clear trend towards unobtrusive lighting systems. Track systems are often used in these environments as they offer a lot of flexibility. The tracks are used to build the basic infrastructure for both the fixing and the powering of the lamps. There are a few disadvantages to this system i.e.:
With most current systems the lamps hang underneath the rail. In case of a retail environment where oftentimes spots are used this means that there are a lot of high power (3000 lm) lamps are attached to the rail and directed onto their targets (like shelves or mannequins). This results in a visually disturbed picture: a rail with lamps hanging underneath it all directed into different directions. This attracts undesirable attention, as the focus of the customers should be on the products that are for sale.
In current track based systems the light module is attached to the track with some sort of clamp. Attaching the lamp to the track or moving the module is often difficult to do. It requires two hands and pressure from the hand to close or release the clamp and all of this above your head standing on a ladder. Moreover, the clamp regularly also establishes the electrical connection, so when the lamp can be moved the light is off and there is no feedback on the actual movement of the light-effect. This lack of ease-of-use limits the shop owner or lighting designer to adjust the lighting on the fly as they see fit after the system has been installed. This for example would be desirable when the shop owner decides to move around some furniture when updating the store or when a lamp needs to be replaced by another one which is more suitable in the new situation.
Current track based lighting systems have lamps hanging underneath a rail. This makes it difficult to light something on the ceiling as this will require the light to be redirected from a downwards direction into an upwards direction. Furthermore, the strip itself will be in the light path, hampering a uniform or light projection on the ceiling.
Track based lighting systems having a pair of equidistant electric conductive (metallic) cables as rails for mounting of the lamps have the disadvantage that said cables itself are not rigid and thus have to be mounted with great tension to give them some rigidity rendering the installation of such lighting system relatively complex and cumbersome. Furthermore, the tensioned, equidistant cables are still susceptible to vibrations and/or moving apart already by relatively small forces. This generally is counteracted by connecting the equidistant cables by bridges, but then these bridges need to be spaced apart at such small distances that the free moving and positioning of lighting modules on said track are significantly hampered.
As mentioned above, in modern lighting systems there is a need to have a great deal of flexibility in the user's ability to easily control the quantity, direction, and characteristics of the light emitted from the system. In theater settings, one is accustomed to observing a number of light fixtures capable of directing light of varying intensities, color, and other characteristics onto the stage. In commercial settings, adjustable reflector lamps and track lights are frequently employed to illuminate merchandise or displays. In office and residential settings, track lights are typically used to direct light to a particular work area or for visual effect. In applications where the appearance of the lighting system itself contributes to its overall aesthetics, there are additional design and production costs. A lighting system comprising a track with a removable lighting module and fulfilling the abovementioned issues is known from U.S. Pat. No. 7,806,569. In the known lighting system the lighting module is mounted on a track by an attractive force between magnetic material of the light module and magnetic material of the track such that a light module may be installed on, removed from, or relocated on the track manually without tools or permanent electrical connection.
Yet this known system has disadvantages. One disadvantage is that while this system is flexible, it still is cumbersome to adjust for different lighting requirements due to the presence of relatively high permanent magnetic forces intended to hold the lighting module in fixed position onto the track. Another disadvantage of the known lighting system is that with the known lighting system it is relatively cumbersome to change the lighting characteristics of the light issued by the lighting system. When the lighting system is used to fit in false ceilings, the lighting module suspends from said track and is attached to it only by magnetic force, said force must thus be high enough to prevent the lighting module to detach from the track, even during shocks. Another disadvantage of the known lighting system is that this it is relatively costly because of the use of (relatively strong) magnetic materials. Finally, there is the disadvantage of the known lighting system that it is obtrusive due to the lighting module protruding from the track. As the lamps hang underneath the track, the rail itself will be in the light path, hampering a uniform or light projection on the ceiling.